/**
 * 商城前台 AJAX 封装
 *
 * 提供统一的 XHR 请求方法、购物车操作、签到、工单提交等。
 * 依赖：页面中需有 <meta name="csrf" content="..."> 或全局变量 FNW_CSRF
 */
var Fnw = (function () {
    'use strict';

    // ─── CSRF Token ───
    function getCsrfToken() {
        var m = document.querySelector('meta[name="csrf"]');
        return m ? m.getAttribute('content') : (window.FNW_CSRF || '');
    }

    // ─── 通用 XHR ───
    /**
     * 发送请求
     * @param {Object} opts
     * @param {string} opts.action - API action 名称
     * @param {string} [opts.method='GET'] - HTTP 方法
     * @param {Object} [opts.data] - POST 数据
     * @param {function} [opts.success] - 成功回调 (res)
     * @param {function} [opts.error] - 失败回调 (res)
     * @param {function} [opts.complete] - 完成回调
     */
    function request(opts) {
        var method = (opts.method || 'GET').toUpperCase();
        var url = 'api.php?action=' + encodeURIComponent(opts.action);
        var xhr = new XMLHttpRequest();
        xhr.open(method, url, true);
        xhr.setRequestHeader('Accept', 'application/json');
        xhr.setRequestHeader('X-Requested-With', 'XMLHttpRequest');

        if (method === 'POST') {
            xhr.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
        }

        // CSRF header for POST
        if (method === 'POST') {
            xhr.setRequestHeader('X-CSRF-Token', getCsrfToken());
        }

        xhr.onreadystatechange = function () {
            if (xhr.readyState !== 4) return;
            if (opts.complete) opts.complete();
            if (xhr.status === 0) { if (opts.error) opts.error({ ok: false, msg: '网络错误，请检查连接' }); return; }
            var res;
            try { res = JSON.parse(xhr.responseText); } catch (e) { res = { ok: false, msg: '服务器响应异常' }; }
            if (res.ok) {
                if (opts.success) opts.success(res);
            } else {
                if (opts.error) opts.error(res);
            }
        };

        if (method === 'POST' && opts.data) {
            var params = [];
            // Always include csrf_token in POST body as fallback
            opts.data.csrf_token = getCsrfToken();
            for (var k in opts.data) {
                if (opts.data.hasOwnProperty(k)) {
                    params.push(encodeURIComponent(k) + '=' + encodeURIComponent(opts.data[k]));
                }
            }
            xhr.send(params.join('&'));
        } else {
            // Append GET params
            if (opts.data && method === 'GET') {
                var qs = [];
                for (var k in opts.data) {
                    if (opts.data.hasOwnProperty(k)) {
                        qs.push(encodeURIComponent(k) + '=' + encodeURIComponent(opts.data[k]));
                    }
                }
                if (qs.length) url += '&' + qs.join('&');
            }
            xhr.send();
        }
    }

    // ─── Toast 提示 ───
    var toastTimer = null;
    function showToast(msg, type) {
        type = type || 'ok'; // 'ok' | 'err' | 'info'
        var existing = document.getElementById('fnwToast');
        if (existing) existing.remove();

        var el = document.createElement('div');
        el.id = 'fnwToast';
        el.className = 'fnw-toast fnw-toast-' + type;
        el.innerHTML = '<span class="fnw-toast-icon">' +
            (type === 'ok' ? '&#10003;' : type === 'err' ? '&#10007;' : '&#9432;') +
            '</span><span class="fnw-toast-msg">' + msg + '</span>';

        Object.assign(el.style, {
            position: 'fixed',
            top: '-60px',
            left: '50%',
            transform: 'translateX(-50%)',
            zIndex: '9999',
            padding: '12px 24px',
            borderRadius: '10px',
            fontSize: '.92rem',
            fontWeight: '500',
            display: 'flex',
            alignItems: 'center',
            gap: '8px',
            boxShadow: '0 8px 24px rgba(0,0,0,.15)',
            transition: 'top .3s ease',
            maxWidth: '90vw'
        });

        var colors = {
            ok:   { bg: '#f0fdf4', border: '#86efac', color: '#166534', icon: '#22c55e' },
            err:  { bg: '#fef2f2', border: '#fca5a5', color: '#991b1b', icon: '#ef4444' },
            info: { bg: '#eff6ff', border: '#93c5fd', color: '#1e40af', icon: '#3b82f6' }
        };
        var c = colors[type] || colors.info;
        el.style.background = c.bg;
        el.style.border = '1px solid ' + c.border;
        el.style.color = c.color;
        el.querySelector('.fnw-toast-icon').style.color = c.icon;

        document.body.appendChild(el);

        // Animate in
        requestAnimationFrame(function () {
            el.style.top = '20px';
        });

        clearTimeout(toastTimer);
        toastTimer = setTimeout(function () {
            el.style.top = '-60px';
            setTimeout(function () { el.remove(); }, 320);
        }, 2800);

        return el;
    }

    // ─── 购物车 ───
    var cart = {
        add: function (productId, qty, callback) {
            request({
                action: 'cart_add',
                method: 'POST',
                data: { product_id: productId, qty: qty || 1 },
                success: function (res) {
                    showToast(res.msg || '已加入购物车', 'ok');
                    cart.updateBadge(res.data.cart_count);
                    if (callback) callback(null, res.data);
                },
                error: function (res) {
                    showToast(res.msg || '加入购物车失败', 'err');
                    if (callback) callback(new Error(res.msg));
                }
            });
        },
        update: function (productId, qty, callback) {
            request({
                action: 'cart_update',
                method: 'POST',
                data: { product_id: productId, qty: qty },
                success: function (res) {
                    cart.updateBadge(res.data.cart_count);
                    if (callback) callback(null, res.data);
                },
                error: function (res) {
                    showToast(res.msg || '更新失败', 'err');
                    if (callback) callback(new Error(res.msg));
                }
            });
        },
        remove: function (productId, callback) {
            request({
                action: 'cart_remove',
                method: 'POST',
                data: { product_id: productId },
                success: function (res) {
                    showToast('已移除', 'ok');
                    cart.updateBadge(res.data.cart_count);
                    if (callback) callback(null, res.data);
                },
                error: function (res) {
                    showToast(res.msg || '移除失败', 'err');
                    if (callback) callback(new Error(res.msg));
                }
            });
        },
        clear: function (callback) {
            request({
                action: 'cart_clear',
                method: 'POST',
                success: function (res) {
                    showToast('购物车已清空', 'ok');
                    cart.updateBadge(0);
                    if (callback) callback(null);
                },
                error: function (res) {
                    showToast(res.msg || '清空失败', 'err');
                    if (callback) callback(new Error(res.msg));
                }
            });
        },
        updateBadge: function (count) {
            var badges = document.querySelectorAll('.badge.cart-badge');
            badges.forEach(function (b) {
                b.textContent = count;
                b.style.display = count > 0 ? 'inline' : 'none';
            });
            // Also try nav-link badge
            var navBadge = document.querySelector('a[href="cart"] .badge');
            if (navBadge) {
                navBadge.textContent = count;
                navBadge.style.display = count > 0 ? 'inline' : 'none';
            }
        }
    };

    // ─── 签到 ───
    var sign = {
        do: function (callback) {
            request({
                action: 'sign_in',
                method: 'POST',
                success: function (res) {
                    showToast(res.msg || '签到成功！', 'ok');
                    if (callback) callback(null, res.data);
                },
                error: function (res) {
                    showToast(res.msg || '签到失败', 'err');
                    if (callback) callback(new Error(res.msg));
                }
            });
        }
    };

    // ─── 工单 ───
    var ticket = {
        submit: function (data, callback) {
            request({
                action: 'ticket_submit',
                method: 'POST',
                data: data,
                success: function (res) {
                    showToast(res.msg || '工单提交成功！', 'ok');
                    if (callback) callback(null, res.data);
                },
                error: function (res) {
                    showToast(res.msg || '提交失败', 'err');
                    if (callback) callback(new Error(res.msg));
                }
            });
        }
    };

    // ─── 搜索（防抖）─────────────────────────────────────────────
    var searchTimer = null;
    var search = {
        /**
         * 带防抖的搜索
         * @param {string} q 关键词
         * @param {number} [delay=400] 防抖毫秒数
         * @param {function} callback 回调 (err, results)
         */
        query: function (q, delay, callback) {
            if (typeof delay === 'function') { callback = delay; delay = 400; }
            clearTimeout(searchTimer);
            if (!q || q.length < 1) { if (callback) callback(null, []); return; }
            searchTimer = setTimeout(function () {
                request({
                    action: 'search',
                    data: { q: q },
                    success: function (res) { if (callback) callback(null, res.data); },
                    error: function (res) { if (callback) callback(new Error(res.msg)); }
                });
            }, delay);
        }
    };

    // ─── 公开 API ───
    return {
        request: request,
        toast: showToast,
        cart: cart,
        sign: sign,
        ticket: ticket,
        search: search,
        csrf: getCsrfToken
    };
})();

// ─── 页面加载后初始化：注入 CSRF meta ───
(function () {
    // 如果页面还没有 csrf meta tag，尝试从表单中获取并注入
    if (!document.querySelector('meta[name="csrf"]')) {
        var csrfInput = document.querySelector('input[name="csrf"]');
        if (csrfInput) {
            var meta = document.createElement('meta');
            meta.name = 'csrf';
            meta.content = csrfInput.value;
            document.head.appendChild(meta);
        }
    }
})();